Maybe this has been addressed before, but it seems to me the CB would be the biggest drag on site performance. To use CB, you have to constantly refresh the screen but making yet another web page request. I'd be willing to bet that if CB was off, general site performance would improve radically (not that I'm suggesting removing CB).

Moving on to the "not this again" section. Is there a way to make CB refresh automatically (using perl, not Java)? If that was the case, then there would be far fewer page requests, as people wouldn't bounce around just to refresh CB.